1. Field of the Invention
The present invention relates to a goods drop out device and method therefor. More particularly, the invention relates to a goods drop out device suitable for picking of goods in a goods delivery center and so forth.
2. Prior Art
(A) As disclosed in Japanese Unexamined Utility Model Publication No. 2-86903, a conventional goods picking device employs goods receptacle portions defined in a drop out box and opening and closing devices for opening and closing bottoms of the goods receptacle portions so that the goods can be dropped out of each goods receptacle portion by an opening operation of the opening and closing device onto a collecting conveyer or so forth.
Here, in the conventional goods drop out device, the opening and closing device comprises an opening and closing member for opening and closing the bottom of the goods receptacle portion by movement in parallel to the bottom, and an opening and closing cylinder assembly for shifting the opening and closing member in a range where the opening and closing member is permitted to open and close the bottom of the goods receptacle portion.
However, in the prior art, when the sizes of the goods to be objects of dropping out are different from each other, the arrangement pattern of the goods receptacle portion defined in the drop out box can be differentiated resulting in a difference of the size of the bottom opening of each goods receptacle portion to be opened and closed by the opening and closing member, and thus in a difference of the range of movement of the opening and closing member to accordingly differentiate the stroke length of the opening and closing cylinder assembly. Namely, in the prior art, for drop out devices adapted to drop out mutually different sizes of goods, opening and closing cylinder assemblies having different stroke lengths are required.
An object of the invention is to improve efficiency of facility by enabling to certainly open and close a bottom opening and closing member for goods receptacle portions having mutually different bottom opening sizes employing an opening and closing cylinder assembly having a uniform stroke length.
(B) On the other hand, in the conventional goods picking device, dropping out of the goods onto the collecting conveyer or so forth is by storing the goods in a plurality of goods receptacle portions defined by partitions inserted into the drop out box and by opening operation of the opening and closing devices.
Here, as disclosed in Japanese Unexamined Utility Model Publication 2-86903, in the conventional goods dropping out method, the opening and closing member corresponding to each individual goods receptacle portion defined in the drop out box by means of partitions is provided so that the opening and closing member corresponding to the individual goods receptacle portion is operated to open upon dropping out of the goods in each goods receptacle portion.
However, in the prior art, it has been required to provide the opening and closing member and the their driving portion for each of the goods receptacle portions. Accordingly, between the drop out devices for respectively different sizes of the goods as objects for dropping out and having different arrangement patterns of the goods receptacle portions defined in the drop out boxes, the installation condition of the opening and closing members and the driving portions therefore should be mutually different. Therefore, in the prior art, in order to enable dropping out of various sizes of goods, it becomes necessary to provide a plurality of kinds of drop out devices for respective sizes of the goods, which are differentiated not only in the arrangement of the partitions in the drop out boxes but also in the installation manner of the opening and closing members and the driving portions therefor, thus lowering efficiency of facility.
An object of the invention is to improve the efficiency of facility by enabling dropping out of various sizes of goods employing the drop out devices having common basic constructions.
(C) On the other hand, as disclosed in Japanese Unexamined Utility Model Publication No. 2-86903, the conventional picking device receives the goods in a plurality of goods receptacle portions defined in matrix form in the drop out box, moves a larger opening and closing member which can open and close the bottoms of respective goods receptacle portions simultaneously per one column, is moved per column, operates smaller opening and closing members arranged at the tip end of the larger opening and closing member and independently opening and closing the bottoms of respective individual goods receptacle portions to open and close and thus drops out the goods in respective goods receptacle portions onto the collecting conveyer or so forth.
Here, in the conventional goods dropping out method, when the number of goods left in the leading column among the columns in which the goods are maintained, is less than a necessary number, a number of the smaller opening and closing members corresponding to the number derived as a remainder after subtracting the maintained number of goods in the leading column and subtracting the number of goods per column (for example number of goods in n columns), are held open, and the larger opening and closing members of the leading column and n columns are moved simultaneously to enable the necessary number of goods to be dropped out.
On the other hand, in the conventional goods dropping out method, when the sizes of the goods to be dropped out are differentiated, the arrangement patterns of the goods receptacle portions defined in the drop out boxes are differentiated so that the sizes of the bottom openings of respective goods receptacle portions to be opened and closed by the smaller opening and closing members are differentiated. Then, it can be considered to improve the efficiency of the facility by adapting the length of the smaller opening and closing member in the motion direction of the larger opening and closing member to an arrangement pattern having an average length in that direction and by using the smaller opening and closing members of this length in common to the arrangement pattern of the other goods receptacle portions of different lengths in that direction.
However, the conventional goods drop out method, in which the smaller opening and closing member of an average length is to be used in common to various arrangement patterns of the goods receptacle portions, and the smaller opening and closing members and the larger opening and closing members are operated in the manner set forth above, is not efficient for the arrangement pattern having a large number of columns due to small size of the goods. Namely, in the arrangement pattern having a large number of columns for small size goods, the tip end portions of the smaller opening and closing members can extend beyond the corresponding goods receptacle portions to partly block the bottoms of the goods receptacle portions in the adjacent column. As a result, when the larger opening and closing members are moved simultaneously for dropping out the goods, not all of the goods receptacle portions which are to be opened by the smaller opening and closing members can be opened sufficiently. Therefore, it becomes impossible to drop out with certainty a necessary total drop out number.
An object of the invention is to enable to drop out with certainty a necessary total number when the common configuration of the smaller opening and closing members are designed to be used in common for various arrangement patterns of the goods receptacle portions.